Roof tile

ABSTRACT

A roof tile  1 , having a length, a width and a height, has an upwardly extending elongate passage  6  having a substantially unobstructed pathway from an outlet  4  at the lower end of the passage to an inlet  2  at an upper end of the passage. A downwardly extending passage  7  communicating with the inlet  2  and adapted to connect to a duct creating a flow path through the passage, through the inlet and along the tile to the outlet. The upwardly extending passage  6  is substantially the length and width of the tile and has a substantially greater width than height.

FIELD OF THE INVENTION

The present invention relates to the provision for ventilation of exhaust gases from within a building having a tiled roof. Usually the exhaust gases take the form of air containing undesirable odours or moisture.

BACKGROUND

Ventilation through roofing is commonly used to remove heat, moisture or undesirable odours from within a building. In the case of a tiled roof this is typically achieved by a tubular structure extending vertically through the tiles. This necessitates cutting tiles and fitting flashing around the tubular structure. The tubular structure is unsightly especially those fitted with a cover to prevent ingress of large objects.

Problems also arise when exhaust gases from inside a building, for example from a bathroom or kitchen, are extracted into the roofing cavity. These exhaust gases are often not fully extracted from the roofing cavity due to many factors including poor circulation and/or ventilation despite having a roof ventilation structure. This can create some problems, for example increased moisture in the roofing cavity which increases mould growth and may produce undesirable smells which are hard to remove.

To overcome the aesthetic problems, roof tiles with flow passages through the body of the tile have been used. These are typically moulded to the profile of the existing roof tiles and simply substituted for original roof tiles.

For example, UK patent application 2 262 295 shows a roof ventilating tile of the same shape and size as a conventional roof tile. The tile has a through duct which opens at opposite ends of the tile. The tile is intended to be laid so that the duct is open to the exterior at the lower end of the tile and is open to the interior of the roof at the upper end. In another example, UK patent application 2 279 675 shows a hollow roofing tile which is shaped externally identically with adjacent solid tiles.

Roof tiles with duct connections have been used to connect exhaust ducts to the roof tiles. For example GB 2 262 949 shows a ventilator for a tiled roof with a circular-section pipe, however the ventilator does not match the existing tiles. In another example, WO 98/15701 shows a covert roof ventilator with an upper wall of shape complementary to roof tiles with which it is to be used. The ventilator also has an apertured lower wall spaced form the upper wall with an elongate aperture formed at a toe portion of the ventilator having a combined grill and baffle. A spigot extends from the aperture which when in use may be connected to a soil pipe. The grill prevents the ingress of small mammals and birds to the inside of the ventilator while the baffle prevents the ingress of driven rain and snow. An upstanding wall further prevents the ingress of driven rain and snow. The baffle and wall mean greater complexities in the manufacturing process including more intricate mouldings. Further the baffle and wall creates a complex flow path for the exhaust gases. Additionally a separate upper wall is required for each style of tile. This leads to uneconomical production costs and assembly problems.

Therefore it would be desirable for a roof tile to remove the exhaust gas from the building directly to the outside of the roof, be aesthetically pleasing whilst being simple in construction.

SUMMARY OF THE INVENTION

Accordingly in one aspect the present invention is a roof tile, having a length, a width and a height, including an upwardly extending elongate passage having a substantially unobstructed pathway from an outlet at the lower end of the passage to an inlet at an upper end of the passage, a downwardly extending passage communicating with the inlet and adapted to connect to a duct. The upwardly extending passage is substantially the length and width of the tile and has a substantially greater width than height.

Preferably, the downwardly extending passage is adjacent the inlet on the side of the inlet remote from the outlet. Even more preferably the inlet is located below the course of roof tiles above the roof tile.

Preferably, the roof tile includes an insect barrier.

Preferably the downwardly extending passage is orientated perpendicularly to the upwardly extending passage. Preferably, the downwardly extending passage is cylindrical. Even more preferably, the downwardly extending passage is adapted to be able to be connected to at least two different sized ducts.

Preferably the roof tile is made from metal, plastic or a combination of metal and plastic. In one embodiment, when the roof tile is made of plastic, the roof tile includes a light transmitting portion. The roof tile may also be adapted to be attached to a light conveying duct.

DETAILED DESCRIPTION

Some of the embodiments of the invention will now be described with reference to the following drawings:

FIG. 1—A perspective view of the outer surface of a roof tile according to one embodiment of the invention.

FIG. 2A—A cross-sectional view B-B of the roof tile shown in FIG. 1.

FIG. 2B—A cross-sectional view B-B of the roof tile shown in FIG. 1.

FIG. 3—A cross-sectional view A-A of the roof tile shown in FIG. 1.

FIG. 4—A perspective view of a roof tile according to another embodiment of the invention.

FIG. 5—A plan view of the underside of a roof tile according to another embodiment of the invention showing attachment lugs.

FIG. 6—A representative drawing of the roof tile as shown in FIG. 1 installed in a tiled roof.

The roof tile of the present invention is suited to enable ducted exhaust gases to an outside space through an inclined tiled roof. The roof tile replaces an existing normal tile and is ideally connected to an exhaust gas duct.

Referring to FIG. 1, the roof tile 1 generally has the same shape as the existing roof tiles. It is generally rectangular in shape being defined by a length, a width and a height. Generally such tiles have a greater length than width and a substantially greater width than height. For example a length:width:height ratio of 16:12:1 is common.

The roof tile has an inlet 2 near the upper end 3 and outlet 4 at the lower end 5. When installed, the inlet 2 is vertically displaced from the outlet 4. An upwardly extending passage 6 extends from the outlet 4 to the inlet 2. This passage is substantially unobstructed allowing generally free air flow from the inlet 2 to the outlet 4. In one embodiment this passage extends the full length of the tile. A downwardly extending passage 7 is connected to the inlet 2 and is adapted to be connected to a duct, not shown. As a consequence, the flow path is from the passage 7 through the inlet and along the length of the tile to the outlet.

The downwardly extending passage 7 is designed to reduce the flow resistance of exhaust gas when the air flow is in the direction from the inlet 2 to the outlet 4. It is also designed to increase the flow resistance when the air flow in the direction from the outlet 4 to the inlet 2.

The design and position of the downwardly extending passage 7 varies from application to application depending upon various factors such as the exhaust gas temperature, pressure and flow rate, and physical limitations on the passage such as a roofing truss support or additional devices in the roofing cavity eg hot water service. The position of the downwardly extending passage 7 is generally at or near the upper end 3 of the roof tile 1. As shown in FIG. 6, the roof tile 61 may extend beyond the normal length of the roof tiles so that the inlet 62 and downwardly extending passage 63 are below the course of tiles above the roof tile 64 when installed on the roof. The cross-section of the downwardly extending passage could also be any suitable shape, for example rectangular, square or circular.

A sealing section 8 can be shaped to conform to the profile 9 of the existing tiles. Shaping of the sealing section 8 may be done by cutting away part of the sealing section 8 so that the profile 9 is obtained. For example, the profile 9 could be obtained by abutting an existing tile end to the sealing section 8, marking the profile 9, removing the existing tile and cutting along the profile markings 9 using tin sips. The shaped sealing section 65 is shown in FIG. 6. This shape conformable sealing section means that the tile can be installed universally regardless of the shape of the existing tiles.

Referring to FIG. 2A, the flow of an exhaust gas 20 through the roof tile 21 can be seen by arrows indicating the direction of the flow. The exhaust gas may be from an apparatus within the roofing cavity, such as a heating/cooling apparatus, or from an internal space in the building, such as a bathroom. The exhaust gas may contain water and any other material which could cause an unpleasant odour or condition in the roofing cavity.

One example is a bathroom exhaust fan which extracts steam from a bathroom so that the mirrors in the bathroom do to not fog up with the steam whilst having a hot shower. The steam may collect in the roofing cavity if the cavity does not have adequate ventilation and create a build up of water from the condensed steam. This may cause problems such as weakening of ceiling plaster, unsightly damp spots in the ceiling of the building, and mould growth, which may cause health problems. All of these problems are undesirable in many buildings.

In the embodiment shown in FIG. 1, a duct would be connected to the exhaust fan so that the extracted steam would flow through the duct to the downwardly extending passage of roof tile, through the upwardly extending passage and out to the atmosphere. This eliminates any additional dampness in the roofing cavity from the bathroom steam.

Referring to FIG. 2B, air flow from the atmosphere 22, such as wind, is restricted due to the length of the roof tile 23. This is without the need for additional baffles or complexity in the construction of the roof tile 1.

Referring to FIG. 3, the roof tile 30 includes an outer section 31, an underneath section 32. This construction allows for a simple yet strong tile to be formed. A central brace 33 may also be included to strengthen the exhaust roof tile 30. The upwardly extending passage 34 extends the width and height of the roof tile 30.

The outer section 31 and underneath section 32 can be joined by any appropriate means such as welding, including resistance spot and laser welding, or by mechanical means such as screws, bolts or rivets.

Referring to FIG. 4, the roof tile 40 includes an outer section 41, an underneath section 42 and a sealing section 43. A mesh 46 may also be included near the lower end 44 to prevent foreign materials, for example insects, from travelling up the roof tile 40. The roof tile also includes a downwardly extending passage 45 which is connected to the outer section 41 and underneath section 42 and is adapted to be connected to a duct, not shown.

It may also be necessary for a sealant to be applied around the exhaust roof tile 40 when installed to increase the weather resistance of the roof. Further it may also be necessary for sections of the tile or tiles above the exhaust roof tile to be removed so that a flat surface is on the underside of the tile or tiles is obtained.

The roof tile can be made from any suitable material for example plastic or metal. A roof tile made from a metal may also have a protective coating, for example zinc coated steel or galvanised steel. Zincanneal® made by BHP Steel has been found to be beneficial in certain circumstances as it is fire resistant, especially in bush fire prone areas. The roof tile may then be painted to match the colour of the existing roof tiles so as to be more aesthetically pleasing. A roof tile made from plastic is also beneficial as the weight of the tile is reduced. A plastic roof tile also allows for colouring and more intricate shapes to be formed through moulding. However, a combination of metal and plastic components whilst maintaining the advantages of both materials is also beneficial. For example, having a body made from metal provides fire resistance and the downwardly extending passage from plastic so as to involve more intricate shaping is especially beneficial.

A roof tile made from plastic may also include a light transmitting portion, for example a transparent plastic portion, to provide light to the roof cavity or another part of a building when attached to a light conveying duct. Alternatively the tile may be made form a non opaque plastic, for example polycarbonate or acrylic. The light conveying duct can be attached to the roof tile by any suitable means, for example by screws, rivets or otherwise. Referring to FIG. 5, the roof tile 50 is provided with lugs 51 so as to attach a light conveying duct to the roof tile without the need for any further fastening. However, if required, the light conveying duct can be fastened to the roof tile by both the lugs and additional means such as screws. The light conveying duct can then connected to a diffuser in an enclosed room of the building, providing natural light into that room.

The foregoing describes only certain embodiments of the present invention and modifications, obvious to those skilled in the art can be made thereto without departing from the scope of the present invention.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge. 

1. A roof tile having a length, a width and a height, including: an upwardly extending elongate passage having a substantially unobstructed pathway from an outlet at the lower end of the passage to an inlet at an upper end of the passage, a downwardly extending passage communicating with the inlet and adapted to connect to a duct, wherein the upwardly extending passage is substantially the length and width of the tile and has a substantially greater width than height.
 2. A roof tile according to claim 1, wherein the downwardly extending passage is adjacent the inlet on the side of the inlet remote from the outlet.
 3. A roof tile according to claim 2, wherein the inlet, in use, is located below the course of tiles positioned above the roof tile.
 4. A roof tile according to claim 1, wherein the roof tile includes an insect barrier.
 5. A roof tile according to claim 1, wherein the downwardly extending passage is orientated perpendicularly to the upwardly extending passage.
 6. A roof tile according to claim 5, wherein the downwardly extending passage is cylindrical.
 7. A roof tile according to any one of claims 1, wherein the downwardly extending passage is adapted to be able to be connected to at least two sized ducts.
 8. A roof tile according to claim 1 wherein the roof tile is made from plastic.
 9. A roof tile according to claim 8 wherein the roof tile includes a light transmitting portion.
 10. A roof tile according to claim 9 wherein the roof tile is adapted to be connected to light conveying duct.
 11. A roof tile according to claim 1 wherein the roof tile is made from metal.
 12. A roof tile according to claim 1 wherein the roof tile is made from a combination of metal and plastic.
 13. A roof tile according to claim 1 wherein the ratio of length to width to height is 16:12:1. 